Discussed are demonstration versions of six reliability prediction software packages: FRATE, MilStress, PC Predictor, REAPmate, ReCalc 2 and RELEX. The programs are compared on the basis of price, data-input process, output-reporting options, error handling, user friendliness, and other options. No attempt is made to rank the programs in any way since any such ranking is highly dependent on the user's perspective and needs. Overall, the programs have many advanced features and provide powerful tools for assessing the reliability of a design.<>
讨论了六个可靠性预测软件包的演示版本:FRATE, MilStress, PC Predictor, REAPmate, ReCalc 2和RELEX。这些程序在价格、数据输入过程、输出报告选项、错误处理、用户友好性和其他选项的基础上进行比较。没有尝试以任何方式对程序进行排名,因为任何此类排名都高度依赖于用户的观点和需求。总的来说,这些程序具有许多先进的功能,并为评估设计的可靠性提供了强大的工具。
{"title":"A comparison of commercial reliability prediction programs","authors":"J. Bowles, L. A. Klein","doi":"10.1109/ARMS.1990.68000","DOIUrl":"https://doi.org/10.1109/ARMS.1990.68000","url":null,"abstract":"Discussed are demonstration versions of six reliability prediction software packages: FRATE, MilStress, PC Predictor, REAPmate, ReCalc 2 and RELEX. The programs are compared on the basis of price, data-input process, output-reporting options, error handling, user friendliness, and other options. No attempt is made to rank the programs in any way since any such ranking is highly dependent on the user's perspective and needs. Overall, the programs have many advanced features and provide powerful tools for assessing the reliability of a design.<<ETX>>","PeriodicalId":383597,"journal":{"name":"Annual Proceedings on Reliability and Maintainability Symposium","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134271020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A method is presented for calculating the operational availability, mean time between failures (MTBF), mean time to repair (MTTR), and mean logistic delay time (MLDT) of a system, given the MTBF, MTTR, and MLDT of the lowest replaceable units (LRUs). The method is applicable to systems that undergo operating and nonoperating periods for an indefinite time. Development of the method required extension of the definitions of MTTR and MLDT at the LRU level to the system level. The method of calculating the system level parameters used a model to calculate inherent ability as an intermediate step. An example is presented that demonstrated a computer program suitable for use by a RAM engineer on design and development projects.<>
{"title":"A model for mean-time-to-repair and mean-logistics-delay-time at the system level","authors":"T. Wing, L. H. Crow","doi":"10.1109/ARMS.1990.67989","DOIUrl":"https://doi.org/10.1109/ARMS.1990.67989","url":null,"abstract":"A method is presented for calculating the operational availability, mean time between failures (MTBF), mean time to repair (MTTR), and mean logistic delay time (MLDT) of a system, given the MTBF, MTTR, and MLDT of the lowest replaceable units (LRUs). The method is applicable to systems that undergo operating and nonoperating periods for an indefinite time. Development of the method required extension of the definitions of MTTR and MLDT at the LRU level to the system level. The method of calculating the system level parameters used a model to calculate inherent ability as an intermediate step. An example is presented that demonstrated a computer program suitable for use by a RAM engineer on design and development projects.<<ETX>>","PeriodicalId":383597,"journal":{"name":"Annual Proceedings on Reliability and Maintainability Symposium","volume":"322 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132313513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Some shortcomings in the industry guidelines MIL-STD-1629A in performing failure mode, effects, and criticality analyses are highlighted. It can be shown that if the MIL-STD-1629A guidelines are followed, then the contribution of several terms to the item-criticality numbers (the final step in completing a criticality analysis) is erroneously omitted. As a result, the item-criticality numbers for the lower severities of the item are incorrect. As a separate issue, a broader definition of beta is recommended to properly treat failures in redundant systems.<>
{"title":"Shortcomings in MIL-STD-1629A guidelines for criticality analysis","authors":"A. Agarwala","doi":"10.1109/ARMS.1990.68007","DOIUrl":"https://doi.org/10.1109/ARMS.1990.68007","url":null,"abstract":"Some shortcomings in the industry guidelines MIL-STD-1629A in performing failure mode, effects, and criticality analyses are highlighted. It can be shown that if the MIL-STD-1629A guidelines are followed, then the contribution of several terms to the item-criticality numbers (the final step in completing a criticality analysis) is erroneously omitted. As a result, the item-criticality numbers for the lower severities of the item are incorrect. As a separate issue, a broader definition of beta is recommended to properly treat failures in redundant systems.<<ETX>>","PeriodicalId":383597,"journal":{"name":"Annual Proceedings on Reliability and Maintainability Symposium","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133748799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The integration into educational programs at Florida Institute of Technology (FIT) of reliability, maintainability, and testability (RMT) material is discussed. FIT, in cooperation with local industry and government, has begun integrating RMT material into the required course structure for their undergraduate electrical engineering and computer engineering students. Faculty and students have readily accepted this additional material and realize its importance if the design challenges of the future are to be met.<>
{"title":"Integrating reliability, maintainability and testability into the undergraduate curriculum","authors":"D.H. Merlino, J. Hadjilogiou, D. Wu","doi":"10.1109/ARMS.1990.67937","DOIUrl":"https://doi.org/10.1109/ARMS.1990.67937","url":null,"abstract":"The integration into educational programs at Florida Institute of Technology (FIT) of reliability, maintainability, and testability (RMT) material is discussed. FIT, in cooperation with local industry and government, has begun integrating RMT material into the required course structure for their undergraduate electrical engineering and computer engineering students. Faculty and students have readily accepted this additional material and realize its importance if the design challenges of the future are to be met.<<ETX>>","PeriodicalId":383597,"journal":{"name":"Annual Proceedings on Reliability and Maintainability Symposium","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134437427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The effect of two parametric failure discounting methods on the accuracy of three discrete and two continuous reliability growth models is analyzed. Similar comparisons are made for two data-weighting methods. Graphs are used to make comparisons on the accuracy of these models without discounting or weighting, with discounting only, and with weighting only. The accuracy comparisons are made using Monte Carlo methods. The results show that cumulative growth models such as the AMSAA and maximum likelihood models have greater bias than the noncumulative regression models for the cases simulated. The results also show that the cumulative models appear to be more sensitive to failure discounting and thus more susceptible to yielding optimistic estimates of reliability than the regression-type models when failure discounting is employed. Failure discounting applied too frequently (e.g. after each successful test) can adversely affect the accuracy of any of the models analyzed.<>
{"title":"The effect of discounting failures and weighting data on the accuracy of some reliability growth models","authors":"W. M. Woods","doi":"10.1109/ARMS.1990.67956","DOIUrl":"https://doi.org/10.1109/ARMS.1990.67956","url":null,"abstract":"The effect of two parametric failure discounting methods on the accuracy of three discrete and two continuous reliability growth models is analyzed. Similar comparisons are made for two data-weighting methods. Graphs are used to make comparisons on the accuracy of these models without discounting or weighting, with discounting only, and with weighting only. The accuracy comparisons are made using Monte Carlo methods. The results show that cumulative growth models such as the AMSAA and maximum likelihood models have greater bias than the noncumulative regression models for the cases simulated. The results also show that the cumulative models appear to be more sensitive to failure discounting and thus more susceptible to yielding optimistic estimates of reliability than the regression-type models when failure discounting is employed. Failure discounting applied too frequently (e.g. after each successful test) can adversely affect the accuracy of any of the models analyzed.<<ETX>>","PeriodicalId":383597,"journal":{"name":"Annual Proceedings on Reliability and Maintainability Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132719712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A methodology for estimating the reliability of weapon systems early in development, even before system testing, has been applied to four types of advanced gun propulsion (advanced solids, liquid propellant, electromagnetic, and electrothermal) for three different weapon system types (artillery, armor, and air defense). The goals were to determine the feasibility of developing a methodology by which the reliability of systems resulting from tech base programs could be estimated and to develop reliability projections of artillery, armor, and air defense weapon systems resulting from the tech base efforts in new propulsion systems. The performance characteristics of the systems are defined, the approach taken in the study is described, and the results are summarized. The numerical reliability results are not intended to be used for determining reliability requirements for these weapon systems but instead to give the system designer a better understanding of those subsystems which are expected to be high risk.<>
{"title":"Propulsion technology effect on weapon system reliability","authors":"F.M. Denicola","doi":"10.1109/ARMS.1990.68010","DOIUrl":"https://doi.org/10.1109/ARMS.1990.68010","url":null,"abstract":"A methodology for estimating the reliability of weapon systems early in development, even before system testing, has been applied to four types of advanced gun propulsion (advanced solids, liquid propellant, electromagnetic, and electrothermal) for three different weapon system types (artillery, armor, and air defense). The goals were to determine the feasibility of developing a methodology by which the reliability of systems resulting from tech base programs could be estimated and to develop reliability projections of artillery, armor, and air defense weapon systems resulting from the tech base efforts in new propulsion systems. The performance characteristics of the systems are defined, the approach taken in the study is described, and the results are summarized. The numerical reliability results are not intended to be used for determining reliability requirements for these weapon systems but instead to give the system designer a better understanding of those subsystems which are expected to be high risk.<<ETX>>","PeriodicalId":383597,"journal":{"name":"Annual Proceedings on Reliability and Maintainability Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116071133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Information is provided concerning built-in test (BIT) and its importance to the military user. The paper is directed at the engineers who design the mission equipment. The discussion points to the need for greater availability in development of weapon systems. To most designers, availability is an unknown and unquantifiable metric that is often ignored. Availability must be defined in terms more easily understood by the design community.<>
{"title":"BIT blueprint toward more effective built-in test","authors":"G. Daugherty, M. Steinmetz","doi":"10.1109/ARMS.1990.67983","DOIUrl":"https://doi.org/10.1109/ARMS.1990.67983","url":null,"abstract":"Information is provided concerning built-in test (BIT) and its importance to the military user. The paper is directed at the engineers who design the mission equipment. The discussion points to the need for greater availability in development of weapon systems. To most designers, availability is an unknown and unquantifiable metric that is often ignored. Availability must be defined in terms more easily understood by the design community.<<ETX>>","PeriodicalId":383597,"journal":{"name":"Annual Proceedings on Reliability and Maintainability Symposium","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122427997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The top-down approach to determining required standby redundancy to improve reliability and to extend mean time between failures is discussed. Simple analytical expressions are derived to capture the essence of the problem. In cases where the values of the parameters can be estimated based on experience with similar systems, the method should allow reasonable early estimates of required standbys. When prior information is not available, required values of the parameters can be determined and used as design requirements. The simple expressions are amenable to programming on pocket calculators and personal computers, allowing rapid evaluation of alternatives during early phases of system design.<>
{"title":"Practical models for determining standby redundancy levels","authors":"R. W. Sears","doi":"10.1109/ARMS.1990.67943","DOIUrl":"https://doi.org/10.1109/ARMS.1990.67943","url":null,"abstract":"The top-down approach to determining required standby redundancy to improve reliability and to extend mean time between failures is discussed. Simple analytical expressions are derived to capture the essence of the problem. In cases where the values of the parameters can be estimated based on experience with similar systems, the method should allow reasonable early estimates of required standbys. When prior information is not available, required values of the parameters can be determined and used as design requirements. The simple expressions are amenable to programming on pocket calculators and personal computers, allowing rapid evaluation of alternatives during early phases of system design.<<ETX>>","PeriodicalId":383597,"journal":{"name":"Annual Proceedings on Reliability and Maintainability Symposium","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116392101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Software safety assurance philosophy and practices at the NASA Ames Research center are discussed. It is shown that, to be safe, software must, for all practical purposes, be error-free. Case histories cover software developments on two digital flight control systems and two ground facility systems. For each case history, the overall system and software organization and function are described and the software-safety issues and their resolution are presented. The effectiveness of safety assurance methods is discussed. Methods include conventional life-cycle practices, verification and validation testing, software safety analysis, and formal design methods for realizing safe software. Three conclusions are drawn: a practical technology for assuring that software is safe does not yet exist, it is unlikely that a set of general-purpose analytical techniques can be developed for proving that software is safe, and successful software safety-assurance practices will have to take into account the detailed design processes employed in the software development and show that the software will execute correctly under all possible conditions.<>
{"title":"Software safety: a user's practical perspective","authors":"W. Dunn, L. Corliss","doi":"10.1109/ARMS.1990.67997","DOIUrl":"https://doi.org/10.1109/ARMS.1990.67997","url":null,"abstract":"Software safety assurance philosophy and practices at the NASA Ames Research center are discussed. It is shown that, to be safe, software must, for all practical purposes, be error-free. Case histories cover software developments on two digital flight control systems and two ground facility systems. For each case history, the overall system and software organization and function are described and the software-safety issues and their resolution are presented. The effectiveness of safety assurance methods is discussed. Methods include conventional life-cycle practices, verification and validation testing, software safety analysis, and formal design methods for realizing safe software. Three conclusions are drawn: a practical technology for assuring that software is safe does not yet exist, it is unlikely that a set of general-purpose analytical techniques can be developed for proving that software is safe, and successful software safety-assurance practices will have to take into account the detailed design processes employed in the software development and show that the software will execute correctly under all possible conditions.<<ETX>>","PeriodicalId":383597,"journal":{"name":"Annual Proceedings on Reliability and Maintainability Symposium","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123267359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
An integrated-circuit reliability simulator has been developed. Model parameters for the reliability simulation are obtained through accelerated tests on specially designed test structures. The design of several test chips and associated experimental results are presented. Reliability simulations are described at the detailed circuit-design level using the SPICE circuit simulator or its derivatives as the key module. A computer-automated characterization system is necessary to extract parameter values for the new degradation models.<>
{"title":"Reliability assurance of application-specific microelectronic circuits","authors":"B. Sheu, Wen-Jay Hsu, V. Tyree","doi":"10.1109/ARMS.1990.67988","DOIUrl":"https://doi.org/10.1109/ARMS.1990.67988","url":null,"abstract":"An integrated-circuit reliability simulator has been developed. Model parameters for the reliability simulation are obtained through accelerated tests on specially designed test structures. The design of several test chips and associated experimental results are presented. Reliability simulations are described at the detailed circuit-design level using the SPICE circuit simulator or its derivatives as the key module. A computer-automated characterization system is necessary to extract parameter values for the new degradation models.<<ETX>>","PeriodicalId":383597,"journal":{"name":"Annual Proceedings on Reliability and Maintainability Symposium","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129145254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}